Grass trimmers are a kind of gardening tools, which are used to trim the lawn. The grass trimmer includes a trimming head. The trimming head rotates at high speed to drive a trimming line mounted thereon to rotate so as to realize the cutting function.
The trimming head includes a spool allowing the trimming line to wind thereon. During the cutting operation, the trimming line is worn away gradually due to wear. After operating for a period, it is needed to change a new trimming line and wind the new trimming line around the spool. For the currently known trimming line, a user needs to rotate the spool manually to wind the trimming line around the spool. The winding operation is inconvenient and the winding speed is slow.
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.